It all starts with the man who designed the Brooklyn Bridge. His grandson - John Roebling II - inherited more than 1,000 acres in Highlands County, and gave it to Richard Archbold, an aviator and explorer of exotic places such as Madagascar and New Guinea. It's now Archbold Biological Station.

The privately-run nature preserve and research facility contains some of the oldest plants in North America. Members of the Florida Wildlife Corridor Expedition came to Archbold to learn its role in protecting and connecting the state's natural treasures.

"I'm standing in the middle of a patch of scrub at the Archbold Biological Station. This area on the Lake Wales Ridge was one of the few parts of Florida that were above water during the last bout of global warming, several thousand years ago. They formed islands that poked above the ancient sea, and you can still see the sand dunes out here, peppered with plants that are spiky and thorny - and very short.

And walking with me through the scrub is Archbold plant ecologist Eric Menges and Florida Wildlife Corridor Expedition member Carlton Ward Jr."

"There's been a lot of changes over time, but the basic vegetation has been very similar for some 20,000 years. And this is very different from, say Minnesota, where there's been glaciation over the same time," says Menges.

Replies Ward: "Or if you're 50 miles to the east or west, where you'd be under water."

Ward and fellow expeditioners Joe Guthrie and Elam Stoltzfus are stopping here for a respite on their journey from the tip of the Everglades to the Okefenokee Swamp on the Georgia state line.

They're trying to create a wildlife corridor connecting the state's remaining natural lands. One of the key parcels is Archbold, which has escaped the conversion to citrus groves that's happened in much of the Lake Wales Ridge.

Menges says many of the plants here are found nowhere else. That can be new sources of medicine - and a rare scrub mint is being eyed as a natural insecticide.

"All plants produce chemicals to reduce how much bugs eat them," he says. "And some of the chemicals that are in scrub plants were new chemicals to science that never had been found and never been manufactured before. It's just another reason these organisms are worth protecting, because they may have direct uses to humans that we don't know about yet."

Also with us is Archbold biologist Reed Bowman. He talks with Ward about some of their findings.

"There's been some work done on the palmettos, suggesting that these are actually some of the longest-lived plants in North America, simply because of their adaptations to fire," says Bowman.

"So what kind of animal species would have been walking around here many thousands of years ago among these same palmetto species? asks Ward.

"You don't have to go very far back - maybe 25,000 years ago - up on the Lake Wales Ridge, you might have seen mastodons, glyptodonts, which were giant armadillos that foraged up here," Bowman replies.

In a way, the Florida Wildlife Corridor Expedition's stop at Archbold is a return to its roots. They saw the need for it three years ago, when several researchers here - including current expedition member Joe Guthrie - tracked a black bear that roamed much of central Florida. He tried to roam north, but couldn't find a way to cross Interstate 4. And that's a problem for the survival of many species.

Later that afternoon, we all gathered at Archbold's conference center to talk about making the corridor a realtiy.

"And the thought was how do we engage the public in this concept," says Archbold director Hillary Swain, "which is very comfortable and familiar to conservationists and scientists - the idea of wildlife corridors - but is not a concept that is broadly understood or appreciated in the general public. Hence the concept of the Florida Wildlife Corridor."

Swain says just as her corner of Florida is interdependent on its neighbors, we all are not islands among ourselves.

"We're dependent on our connection to surrounding ranches," she says. "We're dependent on our connections to other protected areas up and down the Lake Wales Ridge. We're dependent on a flow of species and a flow of genes and a flow of processes like fire and water that come through our site - as are all of our neighboring lands."

Some of those neighboring lands will be the next visit of the Florida Wildlife Corridor Expedition, as they continue their journey this week north to the headwaters of the Kissimmee River.